This film presents two methods of measuring ionization energy: photo-ionization, and electron bombardment. A high vacuum system is used with a simple conductivity cell. The photo-ionization of sodium by the use of a mercury light source and monochromator is carried out. The electron bombardment method is then demonstrated with gaseous sodium, and helium, argon and xenon. Animation shows what occurs on the atomic level during the ionization process. Relation of ionization energy to chemical reactivity is explained.
Collaborator: Professor Bruce H. Mahan, University of California, Berkeley.